3D Printer Scalable XY Dual Motor on Y Belt Drive

Attention please:

This project is only a drawing, I haven't realized the real thing yet, so, before printing or before milling any single part, check well the Sketchup file and check any possible mistake.

3D Printer XY Axis, Belt Drive, scalable.
Version with 2 Motors on Y Axis
Please check .stl file because I am not sure about the exporting into .stl

-Linear Rails: Hiwin HGR 15 or equivalent measurements
-Frame: aluminium Profile 30x30 (to stay cheap).
-Pulleys: HTD 3M 16 Teeth -